In the second official trailer for The Shallows, a young woman named Nancy (Blake Lively) walks down a beach and enters the water with her surfboard. She waves to a couple of other surfers. Suddenly, something grabs her and she goes under. She makes it back to the top, surrounded by a pool of blood and swims to a rock, climbing on it. She screams "Shark!" in the direction of the other two surfers, but it's too late.
The great white shark takes one of the surfers in his jaws, raising him up out of the water. The other surfer swims to the rock and she grabs his arms to pull him up to safety when the shark gets him too. Alone now, Nancy tends to her wounds and waits in vain for someone to show up to help her. As the shark circles, she spots a buoy with a flare gun on it just a few yards away and makes a plan.
